Internet and Email _Class XI

Internet:

Internet is the largest global network connecting millions and billions of computers in a common protocol TCP/IP in order to communicate and share resources. It can link educational organizational, business, government and non-government offices, individual etc.

The internet is the largest computer network in the world, connecting millions of computers. When two computers are connected over the internet they can send and receive all kinds of information such as text, graphics, voice, video and computer programs. The billions of people throughout the world are using the internet at the same time. The internet is formed by joining thousands of smaller networks such as LAN, MAN and WAN.

Therefore, Internet is also called network of networks. The cables telephone link, satellite, microwaves, Bluetooth, WI-FI are used to connect the millions of Computer throughout the world.

Origin of the Internet: In 1969, The Advanced Research Project Agency (ARPA) of American defense department created a network called ARPANET. Originally this network was a very because only three Universities and government agency were connected to it. The ARPANET was restricted only to the searches and the multiuser personals. In 1980's the ARPANET was administrated by National Scientific Foundation so called NSF Net.

Terms Used in Internet

Webpage: -A web page is a document that is connected to the World Wide Web. It is visible by anyone connected to the Internet who has a web browser. The webpages are created by using a programming language called Hypertext Markup Language (HTML). It is commonly including text, graphics and link to other webpages.

Website: - A website is a collection of webpages that are related to each other. A website is created by a web page designer for an organization to give information about business, products and services.

Home pages. A home page is the very first page of a web site. It is the first page that a browser opens when you access a website. It acts as the gateway to the website by providing links to its other pages.

URL (Uniform Resource Locator): - The full form of URL is Uniform Resource Locator. It is the address of a web site or web page on the internet. Each website or webpage on the internet has an unique address.

Example

Name                                                   URL

Supreme Court Nepal                          www.supremecourt.gov.np

Public Service commission Nepal        www.psc.gov.np

Google search engine                           www.google.com

National Examinations Board              http://www.neb.gov.np/

Downloading: - The process of receiving and copying electronic information such as data, files, software, MP3, photos etc. from the website to your computer is called downloading.

Uploading: - The process of transferring a file, webpage, data, software, MP3, photos from yours to the World Wide Web is called uploading.

Search Engine: - It is a program that helps to search information on the internet. The search engine programs are developed to make searching easy and fast on the internet. The search engine allows you to search information based on a keyboard or combination of keyword.

Example:-  google, Bing, yahoo, Alta vista, ask, AOL etc.

Web server: - Webserver can refer to either the hardware (the computer) or the software (the web server program) that helps to deliver web content that can be accessed through the Internet. The most common use of web servers is to host website, Web server has an IP address and possibly a domain name. For example if you enter the URL https://   in your web browser, server then fetches then page name and sends it the browser.

Web browser: -A special type of software is needed to access resource on the internet is called the web browser. A web browser allows us to view,download,upload,surf or access documents (web pages) on the World Wide web

Example: -MozillaFirefox, google chrome, Netscape navigate, Internet explorer

Services of the Internet

1)      E-Business: The full form of the term is electronic business. It is the exchange of goods and services by means of the internet or other computer networks. Electronic business can occur between a user and vendor through online information services, the internet or other electronic forms. The main component of transaction is just electronic data interchange.

Different types of e-Business

                                i.            Business To Business(B2B)

                              ii.            Business To Consumer(B2C)

                            iii.            Business to Government(B2E)

                            iv.            Government-To-Government(G2G)

                              v.            Government-To-Citizen(G2C)

Application

1.      Voice over Internet Protocol (VoIP)   3. Web conferencing   

2.      Internet shop                                        4. Voice mail                                                5. Online marketing

Email: - Email (electronic mail) is a method of exchanging digital messages which included text, voice, video, graphics etc from one address to another. Protocol for sending email is Simple Mail Transfer Protocol (SMTP) and a popular protocol for receiving is POP3. Email can be send and received through an email program such as Microsoft Outlook or via a web page belonging to a web ail provide such as  Gmail, Yahoo mail etc.

Advantages of email

1.      The delivery of message is very fast and cheap.

2.      We can attach like text, audio, video, document etc.

3.      Multiple copies of same message can be sent to a group of people at the same time and can be sent as easily to a single person.

4.      We can check email from any computer in the world. For example while visiting, from a hotel room, in our car etc.

5.      Messages can be easily achieved and stored in a database. We can also search by sender, date, subject or put into separate mailboxes.

6.      It is very easy to paste from other application directly into email document ( for example , a review of a paper found on a website)

Disadvantages

1.      Cannot send physical things such  as money, book etc through email

2.      Electronic mailing system depends on electricity and telephone systems. Thus failure of ay one of them cans prevents the user from sending or receiving E-mails.

3.      Medium for transmitting computer virus.

4.      User of Internet may get unwanted mail(spam, junk)

5.      Slightest error in the address or failure in one of the links between sender and receiver is enough to prevent a delivery.

Different types of email account

There are basically two types of email account:-

1.      POP account: - POP email is accessed using client application in the user computer. The user has to configure the email client application with their user_id and Password. Popular email clients are Microsoft outlook, Mozilla thunderbird, Kmail, opera mail etc. The POP mail client connects the email server and download the new email from the server to user computer so that it can be seen later at any time

Advantages

1.      No need to connect to (server) read old emails and to compose new one.

2.      It secure emails as emails are stored in the local computer not in the remote computer(after downloading from email server by client program)

3.      Advertise and spam mails are automatically blocked by software.

4.      The quantities of emails are not limited since after downloading all emails are stored on local computer.

Disadvantages:-

1.      It is not convenient for users who have to access emails from different places.

2.      During shifting of system or format, managing of all email should take care by self.

3.      Need third party software (client program) to access email from server.

4.      If the local computer is shared, the email can be viewed by other people.

2. Web email account:- The web based email services provides a web page through which the users access the email server. The user can access the mail by logging into web page by providing the username and password. Through the web page the user can view, send and store and manages the emails. Emails server can be accessed from any part of the world using webpage.

Advantages

1.      No need of third party software to view it, simply web browser can access it.

2.      Email account can be accessed from any part of the world( from any computer)

3.      No need to manage emails by user themselves.

Disadvantages

1.      Need to be online every time to view and composed emails

2.      Slow to access email, since every emails should be accessed and download from the server to view it.

3.      Size on email server form one user is limited(hence number of emails are limited).

4.      Web mails consists of large number of advertisement and spam mails. 

Video Conference: - Video conference is conduction a conference between two or more participants at different sites by using computer networks to transmit audio and video data to connect users anywhere in the world as if they were in the same room.each user or group of users who are participating in a video conference typically must have a computer, camera, microphone, a video screen and a sound system. Multipoint videoconference allows there or more participants to set in a virtual conference room and communicate as if they were sitting next to each other.

Telnet: -Telnet is a network protocol that allows a user to connect to remote computers over a TCP/IP network such as Internet. Through telnet, an administration or another computer that is part of the same network. Telnet clients are available for all major operating system such as Mac OS, Windows, UNIX and Linux.

Chatting: - Chatting allows users to talk to another in virtual real time. It is the team time type conversation via computers. That means you can only chat with those people who are currently online. Users communicate by typing messages which are send instantly to another person or group. Example yahoo messenger, MSN messenger, Messenger etc are popular chatting programs.

News group: A newsgroup is a discussion about a particular subject consisting of noted written to a central internet site and redistributed through Usenet. The Usenet is a worldwide network of news discussion groups. Usenet's uses the network news transfer protocol (NNTP). A news group is the online area in which users conduct written discussion about a particular subject. Users can post to existing newsgroups, respond to previous posts and create new newsgroups.

Domain name system (DNS):-In a network environment, the name /address given to a single website or a computer which uniqly identifies the resources is called domain name system.

Type of domain names

a.       Top level domain(TLD) :- In an URL, the first filed is then host name which identities a single computer or organization. The last field of the URL is called top level domain describing the type of organization and services. some of the top level domain includes

.com    commercial

.edu     educational

.gov     government

.int       institutional

.mil      military

.net      Networking provides

.org      organizational

Country level domain

Second level domain name includes the country or the origin of the country. Second level domain comes after the top level domain and separated by a period symbol. Example

.np       Nepal

.au       Australia

.fr        france

.nl        Netherlands

.uk       United kingdom

.us        United States of America      

.in        india   

.sg        Singapore

Protocol: -Protocol are the set of rules, procedures and methods that govern the transmission of data over a communication network. These rules provide a method for orderly and efficiently exchange of data between sender and receiver.

Features: -

·         Break large messages in to a small number of fixed sizes

·         Determine the shortest path for transmission of data tom the destination host.

·         Perform the data formatting according to communication requirement.

·         Control the flow flow data from one point to another.

·         Detect error and ensures the transmission of correct data.

·         Provide necessary data security and data privacy.

·         Keep record of all jobs and data communication that have taken place.

·         Established and terminate the connection properly

·         Provide theorder of precedence of data transmission

Common protocol:-

TCP/IP (Transmission ControlProtocol/Internet Protocol): -TCP/IP is a communication protocol mainly used in internet which defines how electronic device such as computer network device should be connected to the network and how data should be transmitted between them.

Transmission control protocol (TCP): -This is a type of protocol which is responsible for verifying the correct delivery of data between computes

Internet protocol (IP):- This is a type of protocol which is responsible for moving packet of data from node to node. Ip forwards each data packet based on a destination address (IP address).

SMTP (Simple Mail Transfer Protocol):- Simple Mail Transfer Protocol is responsible for sending the email message form source to destination computer.

POP3:- The Post office protocol version 3 is an application layer protocol used by a local email client to retrieve email from a remote server over internet connection.

FTP:-File Transfer protocol is an application layer protocol for transferring files between computer systems. FTP is not a hardware dependent hence it can work anywhere in the network. FTP is built on client-server architecture. FTP client and server exist in the network, where client sends commands t the FTP server and server responds.

HTTP: Http stands for Hyper Text Transfer protocol. Computer on the World Wide Web use the http to talk each other. The communication between the client (browser) and the web server involves requests sent by the client and responses from the server. This request and response between the browser and server is possible with http protocol protection from hackers and data tappers.

Telnet: It allows a user on a remote client machine called Telnet client to access the resource of another machine telnet server.

Intranet: - An internet is a private network within an organization, offices, universities etc. to its staff, employees and students that uses protocols and makes connectivity with internet system,

Differencebetween internet and internet:

Internet	Intranet
It is public global network	It is a private network
It is independent to access and use resource itself.	It is dependent to the internet protocol to communicate and access information.
It suns slower that intranet	It runs faster than internet
Internet users are unlimited all over the world.	Intranet users are limited as employees within  an organization
It is used for all kinds of works	It isused for daily routine works

Extranet: - It is the combination of intranet and internet which can be accessed by outside users over the internet by logging on to the network s with a valid user. ID

Negative impact of Internet

Piracy: - computer related technologies are used for copying, distributing (pirating) software,movie, music,books without permission. Internet is one of the main source of the pirating.

Pornography:-Internet is the main source of pornography. It is the process of viewing adult content like text, image or video.

Theft: - There is a chance of transferring the money from one's account to another's account by hacking password, PIN code etc. Computers and internet also used for stealing valuable information of companies, government organizations etc.

Digital digital: -It is the gap of imbalance of the people, households, business and geographical area who use computer and internet and the people, households, business and geographical area who do not use computer and internet.

Many things such as differences in income, education, geographical location, development, infrastructure, policy of the government, comfort levels with technology are contributing factors to create digital divide by making the separation between those with access to technology resources and those without.

Digital divide is the problem that has been created due to unbalance economic status in the society and if the government does not take appropriate policy it will be widen day by day and may cause a huge problem in coming days.

Digital divide effects the modern society

1.      Economic imbalance

2.      Communication gap

3.      Physical barriers

4.      Lack of awareness about information and technology.

Spamming: - Spamming is the sending of unwanted and useless emails to random people. These emails construct the recipients needlessly. They are illegal and make it hard for people to access their email accounts.

Plagiarism: - It is defined as the copying of another authors language, thoughts, ideas or expression and represent them as own purpose. Internets are used to copy the other person's arts, notes, ideas for own purpose.

Personal information: - If you use the internet, your personal information such as your name, address etc. Can be accessed by other people.